Usually the work barely meets the criteria or essentially cheats to qualify as eligibile. The most famous award whoring of all time is Apple's 1984 ad for Macintosh.
While it's commonly assumed that the famous ad aired only once in its entirety — during the 1984 Super Bowl — the truth is that the ad originally premiered a few weeks earlier. On December 31, 1983, just a few minutes before midnight to be exact, the ad hit the air in Twin Falls, Idaho, on KMVT-TV. The reason behind the peculiar airtime is that the advertising folks over at Chiat/Day (now TBWA\Chiat\Day) wanted the commercial to be eligible for that year's advertising awards.
Here's a pretty good history of the award-whoring ad: